DNA:

• Deoxyribonucleic Acid
• Contains the sugar deoxyribose
• Long term storage of genetic information

For more information about DNA, visit this interactive website: http://www.dnai.org/

DNA Structure:

DNA Replication:

• Takes place in the nucleus
• To start, you need DNA, free DNA nucleotides, and Helicase & DNA polymerase

Step 1: The double helix unwinds and the two strands separate.

• Helicase un-zips DNA

Step 2: Each strand functions as a template upon which a new, missing half is built.

• DNA Polymerase builds new DNA

Step 3: Each new double helix consists of one old and one new strand.

• This mechanism is called semiconservative

Extra Information:

• DNA replication eukaryotes occurs simultaneously at many sites (replication bubbles) on a double helix. This allows DNA replication to occur in a shorter period of time than replication from a single origin would allow.
• Despite its speed (50-500 pairs per second), replication is very accurate. Approximately one mistake occurs with every billion nucleotide pairs. DNA polymerase and DNA ligase proofread the new daughter strands.

For a step-by-step animation of DNA replication, click here: http://www.johnkyrk.com/DNAreplication.html

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RNA:

• Ribonucleic Acid
• Single-stranded nucleic acid that contains ribose
• Three types

Messenger RNA: http://www.daviddarling.info/encyclopedia/M/mRNA.html

• RNA molecule that carries copies of intructions for the assembly of amino acids into proteins from DNA to the rest of the cell

Ribosomal RNA: http://www.daviddarling.info/encyclopedia/R/ribosomal_RNA.html

• type of RNA that makes up the major part of ribosomes

Transfer RNA: http://www.daviddarling.info/encyclopedia/T/tRNA.html

• type of RNA molecule that transfers amino acids to ribosomes during protein synthesis

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Works Cited

• DNA Structure picture came from http://www.chemguide.co.uk/
• mRNA image came from http://www.library.thinkquest.org
• rRNA image came from http://images.wellcome.ac.uk
• tRNA image came from http://www.dna-sequencing-service.com
• information in this acticle came from Prentice Hall's Biology book, written by Kenneth R. Miller and Joseph Levine.